Can procalcitonin help identify associated bacterial infection in patients with severe influenza pneumonia? A multicentre study

Abstract

PCT may help discriminate viral from mixed pneumonia during the influenza season. Levels of PCT less than 0.8 μg/l combined with clinical judgment suggest that bacterial infection is unlikely.

The frequency of influenza and bacterial coinfection: a systematic review and meta‐analysis

“…High statistical heterogeneity of the included studies ( I 2  = 95%) removed confidence in reporting an estimate of the pooled mean proportion of bacterial coinfection through meta‐analysis. Using Cook's distances to identify studies that most greatly affected the heterogeneity and results, we found that seven studies contributed more than 50% of the heterogeneity 29, 31, 34, 39, 40, 45, 46. The proportion of bacterial coinfection among the remaining 20 studies, representing 64% of all patients, was between 11% and 35% ( I 2  = 37%).…”

“…A total of 27 articles encompassing 3215 patients met all the inclusion criteria and were included in the final analysis 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54. Of those 27, only eight studies, with 334 patients, provided the numbers or percentages of each bacterial coinfecting pathogen 28, 32, 33, 34, 38, 43, 46, 47. Thus, these eight studies formed the basis for identifying the most common coinfecting bacterial pathogens (Figure 1).…”

“…Severity of illness varied among studies, but all were focused on hospitalized patients, suggesting a greater than average severity. Eleven of the studies (1007 patients) focused exclusively on patients initially enrolled in an intensive care unit (ICU),32, 34, 35, 38, 39, 41, 42, 44, 46, 47, 51 10 enrolled non‐ICU hospitalized patients (973 patients),30, 33, 36, 37, 40, 43, 45, 49, 53, 54 3 enrolled patients in the emergency department (ED; 135 patients),28, 48, 50 and 2 enrolled patients in a mix of inpatient and outpatient settings (1100 patients) 29, 52. The median sample size was 51 (IQR, 18·5–101), and the mean was 119 (SD: 203), which was driven by three large studies29, 44, 53 that contributed 1958 (61%) of the total number of patients included in this analysis.…”

Staphylococcus aureus Infections: Epidemiology, Pathophysiology, Clinical Manifestations, and Management

“…The median age of those with bacterial coinfection was 43 years, and the mortality rate was 21%. In this setting, procalcitonin levels of Ͼ0.8 g/liter had a sensitivity of 91% for detecting bacterial coinfection (729). However, previously well patients with influenza virus infections are not the only patient group affected by PVL-positive necrotizing pneumonia: in a retrospective review of 15 patients with CA-MRSA CAP, only 1 had evidence of preceding influenza, there was no seasonal pattern, and half of the patients were immunocompromised.…”

“…Staphylococcal PVL-positive necrotizing pneumonia was initially described in young, previously healthy patients with a preceding flu-like illness, with rapid onset of severe symptoms, high fever, leukopenia, cavitary pneumonia, and a fulminant course with mortality rates of 56% (727,728). During the 2009 influenza A virus H1N1 pandemic in France, among 103 patients admitted to the ICU with confirmed influenza A virus H1N1 2009 infections, 48 had bacterial coinfection (54% due to Streptococcus pneumoniae and 31% due to S. aureus) (729). The median age of those with bacterial coinfection was 43 years, and the mortality rate was 21%.…”